1. Field of the Invention
The present relates to a heat transferring object for transferring heat generated by a object to be cooled to a cooling unit as well as to a test board and a test apparatus using the heat transferring object.
2. Related Art
Conventionally, as a heat transferring object for cooling a object to be cooled by transferring heat generated by the object to be cooled to a cooling unit, there has been one using a metal having high thermal conductivity. The object to be cooled is cooled by thermally connecting the object to be cooled and the cooling unit by using the heat transferring object so as to cause heat exchange between the object to be cooled and the cooling unit.
For example, in a test apparatus for testing an electronic device such as a semiconductor circuit, a circuit section of a test board for outputting signals to be fed to the electronic device often gets high temperature because the test board uses a large number of integrated circuits. Then a cooling unit is provided so as to cover the circuit section to cool the circuit section by means of water cooling or the like in the conventional test apparatus.
The test board is connected with a test head for mounting the electronic devices through an intermediary of cables. The test board is connected with the cables through an intermediary of connectors. Therefore, the connector on the test board side must be exposed to the outside of an area covered by the cooling unit.
It is noted that the present applicant is presently unaware of any related patent document, so that its description will be omitted here.
It is conceivable of connecting the test board with the test head by optical cables in transmitting/receiving signals between the test board and the test head at high speed. In such a case, optical connectors are provided in the test board.
The optical connector generates heat because it has a light receiving element, a photoelectric transfer element, a light emitting element or the like. However, the optical connector must be exposed to the outside of the area covered by the cooling unit as described before. Therefore, it cannot be cooled directly by the cooling unit.
In order to cool the object separated from the cooling unit as described above, it has been known to thermally connect the cooling unit with the object to be cooled by using the heat transferring object described above. However, when there is a difference in positional level between the cooling unit and the optical connector, the connection among the cooling unit, the optical connector and the heat transferring object becomes a point-to-point contact and cooling efficiency drops because the conventional heat transferring object is rigid. Still more, the point connecting the cooling unit with the heat transferring object is stressed in such a case.
While the heat transferring object is secured to the cooling unit and the optical connector by screws or the like, the object to be cooled such as a semiconductor circuit is soldered to a board such as a printed board. When the point connecting the cooling unit with the heat transferring object is stressed in such a state, there arises a problem that the soldered part is stressed, thus degrading reliability on the connection.